Article wrapping machine



Sept. 12, 1967 F. MINALGA 3,340,675

ARTICLE WRAPPING MACHINE Filed Sept. 25, 1964 3,340,675 ARTICLE WRAPPING MACHINE Frank Minalga, Haddon Heights, N.J., assignor to Avisun Corporation, Philadelphia, Pa., a corporation of Delaware Filed Sept. 25, 1964, Ser. No. 399,256 1 Claim. (Cl. 53228) ABSTRACT OF THE DISCLOSURE In an article wrapping machine, a whip bar draw-s out a length of wrapping material before it is severed. Air jets issue from the whip bar and blow against the wrapping material to urge the free end thereof into proper position across the path of an article which is to be wrapped.

This invention relates to improvements in wrapping machines of the general type as shown in United States Patent 2,447,560.

In this type of machine an article to be wrapped is advanced from an in-feeding station against a continuous wrapping material and onto a movable carrier. This carrier is then moved to a delivery or wrapping station and in so doing is almost completely enveloped by the wrapping material. Before this applied wrapping material is severed, a length of the wrapping material which is necessary for starting the wrapping of another article is drawn from the supply source. It has been found, however, that when the wrapping material is severed the leading end thereof often remains attached or is attracted to adjacent parts of the wrapping machine or is folded upon itself and thus fails to assume an intended position which extends across the path of an advancing article which is to be wrapped. Accordingly, a primary object of this invention is to provide a generally improved and more satisfactory article wrapping machine.

Another object is to provide an article wrapping machine having means for positively urging the leading end of a continuous wrapping material into a desired position.

Still further objects will appear from the following description.

These objects are accomplished by incorporating into article wrapping machines a novel whip bar having means for positively urging the leading end of a continuous wrapping material into a desired position at the start of each article wrapping operation. More particularly, in wrapping machines in which a continuous wrapping material is at least partially enveloped about an article, the whip bar of the present invention engages with the wrapping material and draws a length thereof which is necessary for starting the wrapping of another article and, after the wrapping material has been severed, urges the newly formed leading end thereof into a desired position for wrapping of another article.

The whip bar of the present invention is of hollow construction and includes an air tube, a plurality of rollers which are mounted on the air tube so as to rotate freely as the Whip bar is moved along and relative to a wrapping material and air jet rings interposed between the ends of the rollers. A compressed gas, such as air, is delivered into the whip bar under pressure and issues therefrom through a plurality of holes which extend radially of the air jet rings and open into an air tube within the whip bar.

These discharging streams of gas are directed to impinge against the leading end of the wrapping material and urge the same away from the whip bar and into a desired position for commencing one article wrapping operation.

The gas may be delivered into the whip bar continuously or intermittently; that is, immediately prior to and/or United States Patent "ice during movement of the whip bar to its original position after a desired length of wrapping material has been drawn from the supply source and severed. Generally, the gas is delivered into the whip bar under a low pressure of about 2 to 3 p.s.i. (pounds per square inch) but this may be varied to suit particular operating conditions.

In the drawing,

FIGURE 1 is a vertical section taken longitudinally through a portion of a machine which embodies the invention, with the parts in positions as assumed after an applied portion of a wrapping material has been severed from its supply source;

FIGURE 2 is a view similar to FIGURE 1 showing the positions of the parts when the machine is about to commence the wrapping of another article;

FIGURE 3 is a front view of a whip bar embodied in the wrapping machine illustrated in FIGURES 1 and 2, with a portion thereof shown in section;

FIGURE 4 is a vertical section taken transversely through the whip bar substantially along the line IV-IV of FIGURE 3; and

FIGURE 5 is a diagrammatic view illustrating the operation of the whip bar shown in FIGURE 3.

Referring now to the drawing, at an in-feeding station of the machine of the present invention articles to be wrapped, as indicated at 11, are advanced along side plates 13 by an intermittently actuated conveyor 15 having spaced flights 17. A carrier 19 receives the articles 11 individually from the conveyor 15 and is pivoted to the machine frame for movement, by suitable means not shown, to and from a position as shown in FIGURES 1 and 2. In its uppermost position, the carrier 19 is aligned with a horizontal plate 21 which, together with side folding plates 23, forms a wrapping or delivery station. As in conventional machines, the articles 11 are advanced from the carrier 19 by a pusher 25 which acts against a backing plate 27.

A continuous wrapping material 29, which is to be applied to the articles 11, is delivered from a suitable source over a plate 31 and onto a feed roll 33 which is generally driven continuously by suitable means, not shown. A hollow whip bar 35 is carried at the ends of arms 37 which are pivoted to the machine frame at 39 and operated by a crank mechanism, not shown, through a link 41. As shown in FIGURES 3 and 4, the whip bar includes an air tube 43, a plurality of freely rotatable rollers 45 having bushings 47, and air jet rings 49 which are interposed between the bushings 47 of adjacent rollers and fixed to the air tube 43 by set screws 51. The air tube 43 is supported between the arms 37 by trunnions 53, which are fixed in place by set screws 54, and is connected by a hose 55 to a source of compressed gas, such as air. The compressed gas is discharged downwardly from the air tube 43 through holes 57 which are drilled into the air jet rings 49 and open into the air tube.

Conventional fixed and swinging cutters 59 and 61, respectively, are provided for severing .a desired length of the wrapping material 29 after it has been snugly clamped between rolls 63 and 65 which depend from the carrier 19 and plate 21.

The improvement provided by the present invention resides in the construction and operation of the whip bar 35, and can be best understood by considering a complete cycle of the above described wrapping machine. At the start of an article wrapping operation, the leading end of the wrapping material 29 is draped between the conveyor 15 and the carrier 19 and across the path of an advancing article 11, as shown in FIGURE 2. With the carrier 19 in its lowermost position, it receives the article 11 from the conveyor 15 whereupon the lower or leading end of the wrapping material 29 is folded between 3 the bottom of the article and the carrier. As the carrier 19 is elevated toward its horizontal position the whip bar 35 engages with the wrapping material and prevents the same from becoming slack as it is enveloped about the top and sides of the article.

Once the carrier 19 is aligned with the plate 21, the wrapping material is clamped between the rolls 63 and 65 after which the whip bar 35 is rapidly lowered, as indicated in FIGURE 1, to draw out the required length of Wrapping material for starting of the next wrapping cycle without applying any strain on the article which has already been partially wrapped. It will be noted that in view of the free rotation of the rollers 45, the whip bar 35 is capable of smooth and uniform movement relative to the wrapping material, regardless of its particular slip characteristics. When the Whip bar 35 reaches its lowermost position the swinging cutter 61 cooperates with the fixed cutter 59 to sever the wrapping material. After being cut, the leading end of the continuous wrapping material starts to fall away from the position shown in FIGURE 1, while the whip bar 35 moves upwardly towards its starting position, as shown in FIGURE 2.

With conventional wrapping machines, once the wrapping material has been cut, as shown in FIGURE 1, considerable difliculty is encountered in having the leading end thereof assume the desired starting position shown in FIGURE 2. In some instances the free end of the wrapping material engages with or remains attached to the whip bar, while in other cases the wrapping material falls onto the conveyor 15, often with the leading end of the Wrapping material being folded upon itself. Under these conditions proper wrapping, and particularly the folding of the wrapping material between the article and carrier, could not be achieved.

The novel whip bar 35 of the present invention has eliminated the above noted objections by causing streams of air or other gas to be discharged through the openings 57 and downwardly against the leading end portion of the wrapping material. These gas streams repel electrostatic or other attractive forces which may exist between the wrapping material and the Whip bar and, more important, counteract the suction effect which is devel oped and tends to draw the leading end of the wrapping material toward and perhaps into contact with the whip bar as it moves upwardly. As a result, after being cut the newly formed leading end of the wrapping material in each instance assumes a desired starting position as shown in FIGURE 2, thus assuring satisfactory and consistent wrapping operations.

In the operation of the above described machine compressed air or other gas may be delivered into the hollow whip bar 35 continuously or intermittently; that is, immediately prior to and during the time that the whip bar 35 moves in an upward direction. Further, the pressure under which such gas is delivered is generally low, in the vicinity of about 2 p.s.i. (pounds per square inch), but may be varied to suit the particular operating conditions.

It is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claim.

I claim:

In an article wrapping machine having a carrier, means for moving said carrier between spaced article in-feeding and wrapping stations, means for delivering a continuous wrapping material, means at the in-feeding station for advancing an article against the wrapping material and onto said carrier and means for severing the continuous wrapping material after the carrier and the article thereon have been moved into the wrapping station, the improvement comprising a hollow whip bar for engaging with the continuous wrapping material, means for moving the whip bar toward the article in-feeding station to draw out a length of wrapping material before such wrapping material is severed, and means for delivering a compressed gas into said whip bar, said whip bar having therein an air tube into which said compressed gas is delivered, said whip bar including a plurality of rollers mounted for free rotation on said air tube, air jet rings interposed between the ends of said rollers and holes in said air jet rings and opening into said air tube for discharging the compressed gas against the leading end of the continuous wrapping material after it has been severed for urging the same away therefrom and toward the in-feeding station.

References Cited UNITED STATES PATENTS 2,727,344 12/1955 Lyon et al 53-210 2,801,508 8/1957 Prince 53230 X 3,248,850 5/1966 Andrews et al 53228 TRAVIS S. MCGEHEE, Primary Examiner.

FRANK E. BAILEY, Examiner.

L. S. BOUCHARD, Assistant Examiner. 

